I was checking out Red State to enjoy some more GOP backstabbing, and came across this gem:
Mid-term elections tend to draw out more-closely engaged voters. This is why 2006 was so bad for us: the news was bad in general and in particular, and Republicans were shooting their own party for the evening news. It is also why 2010 was so very good: a critical mass of people was terrified of the things the Democrats were doing while running loose around the place, and demanded a stop to it.
Demographically, this group trends much whiter, older, and better-informed than the Presidential year electorate.
You see, Republicans do better in mid-terms cuz that’s when the smarter white people vote.